Jacob's crackers
1. adjective
tired, exhausted. Rhyming slang leading to KNACKERED; a variant of CREAM CRACKERED formed on a premier brand of cream crackers UK, 2003
2. noun
the testicles. Also shortened form 'jacobs'. Rhyming slang for KNACKERS; from the branded savoury biscuits. Usage popularised by comedian Joe Pasquale in the television programme I'm A Celebrity, Get Me Out of Here, December 2004 UK, 2004